Cardinal Theodore McCarrick suggested last week that U.S. diplomats need to do more to develop "religious channels" with other nations. And he knows firsthand what he's talking about.

McCarrick, a former Catholic archbishop of Washington, traveled to Iran with an interfaith delegation earlier this year to negotiate for the freedom of two hikers held there as suspected spies. But his primary dealings were not with President Mahmoud Ahmadinejad or other strictly political leaders. They were with Iran's religious leadership.

The delegation spent several days persuading Muslim leaders to support the hikers' release, focusing on the importance of compassion in Islam and even quoting from the Quran.

Two days later, the captives were released.

McCarrick recited this history during a recent speech to illustrate the point that the State Department needs to recognize the value of and need for religious channels in diplomacy — something it has been known to resist in the past.

Religion is a motivating force in the daily lives of people around the world, and it has been for centuries. It plays an influential role in politics and societies, sometimes positive and sometimes negative. In today's globalized world, religion is gaining influence, and this has important political implications.

In her book "The Mighty and the Almighty," former Secretary of State Madeline Albright writes about adjusting the lens through which she viewed the world as she came to comprehend the vitality of religious movements across the globe. She once believed it was a mistake to mix religion and foreign policy, but now says politics and religious values must work together to promote peace.

The art of statecraft, Albright says, requires understanding what matters most to those you are trying to influence — something that "cannot be done without taking religious tenets and motivations fully into account." To this end, she and others have convincingly argued in recent years that Foreign Service officers should be trained about the role of religion in world affairs, including its connection to politics and U.S. interests.

It will become increasingly difficult for America to achieve its foreign policy goals without a firm grasp of the world religious context. Religious literacy is an indispensable part of cultural literacy and is essential to advancing American interests abroad. It is also essential to any successful counterinsurgency campaign.

But beyond increasing knowledge, the U.S. should also create broad networks and partnerships with local leaders — including religious leaders — whose goals match its own. Albright points out that it is important to see religion not just as a threat or a source of conflict, but also as a means to reconciliation, peace and prosperity.

Some committed secularists argue that the First Amendment prohibits engagement with religious groups overseas. This is a gross misreading. Nothing in the Establishment Clause can reasonably be construed to require the State Department to ignore politically relevant religious communities as part of foreign policy. Religious groups around the world are participating in important global conversations and projects involving freedom, economic development, humanitarian aid, democracy and human rights, and the U.S. can't ignore them or refuse to engage these issues whenever there is an intersection with religion.

This doesn't mean American foreign policy should be driven by narrow religious interest groups at home. Rather, it is about developing a healthy understanding and respect for the role of religion in societies around the world where we are engaging.

Secularists also argue that religion is too sensitive to engage — that misunderstandings over religious freedom, foreign missionary activity or traditional religious practices are so potentially explosive that U.S. diplomats should steer clear of religion altogether. Yet strong relationships and understandings with religious leaders could be precisely the key needed to diffuse or smooth over such incidents.

Ignoring religion as part of foreign policy is simply unsafe, unwise and ineffective. Religion is already in the global political mix, and the U.S. must find the smartest and most effective ways to engage and respect it. Doing so will improve foreign policy along both practical and moral dimensions.